Treshnish Isles Auk Ringing Group Report 23rd – 30th June 2018

Guillemot adult with chick (Andrew Carter)

Compiled by Robin M. Ward

Expedition dates: 23rd – 30th June 2018

Expedition members: Robin Ward (Leader), Jurjen Annen, Lila Buckingham, Andrew Carter, Tim Dixon, Chris Heward, Emma Hughes, & Shaun Micklewright

Correspondence: Robin Ward, 15 Church Close, Great Stukeley, Cambridgeshire, PE28 4AP e-mail: [email protected]

CONTENTS

Introduction ...... 3

Map of the Treshnish Isles...... 5

Weather ...... 6

Systematic list of birds for 2018 ...... 7

Systematic list of mammals for 2018 ...... 16

Systematic list of lepidoptera for 2018 ...... 17

Other notable wildlife records ...... 18

Map of census zones – Lunga and Sgeir a’ Chaisteil ...... 20

Breeding seabird census data for the Treshnish Isles in 2018 ...... 21

Breeding seabird numbers for each census zone of Lunga and Sgeir a’ Chaisteil in 2018 ...... 22

Population changes for a selection of breeding species on Lunga, 1994 – 2018 ...... 23

Treshnish ringing totals for 23 – 30th June 2018 ...... 25

Census of shags on Fladda, Treshnish Isles ...... 26

Retrapping adults for survival project ...... 29

Treshnish Isles ringing totals 1971 – 2018 ...... 34

Recent ringing recoveries ...... 36

References ...... 37

Acknowledgements ...... 38

The Expeditions 1971 – 2018 ...... 39

Ring series used on the Treshnish Isles since 1927* ...... 42

TIARG Annual Report 2018 v06/01/19 2

Introduction

Since 1971, the Treshnish Isles Auk Ringing Group (TIARG) has monitored, through ringing and census work, the breeding seabird populations of the Treshnish Isles, Argyll. A summary of the early expeditions is given in Birds on the Treshnish Isles 1971-1995 (Walker & Cooper 1996). Annual reports have been produced since 1996 (see http://tiarg.org). This report summarises the results of the Group’s 41st expedition to the Treshnish Isles, during 23rd – 30th June 2018.

As in previous years, the expedition was based around the village ruins at the northern end of Lunga. The majority of the week’s fieldwork was centred upon Lunga and Sgeir a’ Chaisteil where the annual full seabird census and ringing of specific seabird colonies was carried out. Use of the inflatable boat kindly loaned by the Hebridean Trust, enabled seabird census coverage of the islands between Lunga and Fladda, including Fladda. With much logistic help from Iain & Colin Morrison and crew, expedition members were in addition able to census the seabird colonies on all other islands of the Treshnish Isles in 2018. This year’s census was undertaken as part of Seabirds Count, the fourth census of all breeding seabirds in the U.K., following on from Operation Seafarer in 1969/70, the Seabird Colony Register (SCR) census in 1985-87 and Seabird 2000 in 1998-2002. This is only the second time TIARG have been able to census the entire Treshnish Isles group within a year and in particular, that members have landed on Bac Beg (Little Dutchman).

This year was the thirteenth year of a Shag Retrap Adult Survival study (RAS); this entails ringing each adult with its own uniquely engraved colour-ring so that it can be re-identified in the field in future years. This is part of the British Trust for Ornithology’s (BTO) Integrated Population Monitoring Programme, funded by the UK Government. The Group’s activities were dictated as always by the prevailing weather conditions. The light winds and absence of precipitation allowed the mist netting of Storm Petrels at three localities on Lunga needed as part of the Group’s two Storm Petrel RAS studies.

All TIARG census and ringing data are submitted to two national monitoring programmes, the Seabird Monitoring Programme (JNCC) and National Ringing Database (BTO), respectively. The data supplied are of great conservation value, being the sole means of monitoring the seabird colonies of the Treshnish Isles. The conservation importance of these islands is recognised by their designation by the UK Government as a Special Protection Area for internationally important populations of breeding Storm Petrel Hydrobates pelagicus and wintering Barnacle Geese Branta leucopsis. The islands have also been designated a Site of Special Scientific Interest (SSSI), inter alia for seabird breeding colonies of national importance. Financial support for the monitoring work TIARG undertook in 2018 was provided by the Hebridean Trust (www.hebrideantrust.org), owners of the islands.

In addition to the systematic and targeted census and ringing efforts conducted as an annual commitment, TIARG in May and July 2018 undertook expeditions (40th & 42nd) dedicated to estimating the breeding populations of Manx Shearwater and Storm Petrel respectively. Both surveys funded by Scottish Natural Heritage, included some ringing and will be reported on separately via the website tiarg.org. These are the second ever attempts at making comprehensive surveys of the islands for these two species, the previous in 2000 (Offer 2000) and 1996 (Gilbert & Helmsley 1996) respectively.

TIARG Annual Report 2018 v06/01/19 3

Expedition participants June 2018: (left to right back row) Lila Buckingham, Jurjen Annan, Tim Dixon, Emma Hughes, (left to right front row) Shaun Micklewright, Robin Ward, Andrew Carter & Chris Heward (Sharyn Murray)

TIARG Annual Report 2018 v06/01/19 4

Map of the Treshnish Isles

Positioned approximately 2.5 miles south west of Lunga

TIARG Annual Report 2018 v06/01/19 5

Weather

Meteorological data tabulated below was recorded using a hand-held weather station on Lunga during the period 23rd to 30th June 2018. DATE TIME TEMP WIND PRESSURE CLOUD PRECIPITATION VISIBILITY (°C) (kmph) (mbar) (Oktas) (see below) 23/06/2018 20:40 13.0 8.3 1022.6 3 none Muck 23/06/2018 23:05 12.3 8.6 1022.5 1 none Caliach 24/06/2018 08:20 14.8 7.0 1021.5 8 none Black Cuillins 24/06/2018 14:25 19.2 9.5 1021.4 1 none Rum 24/06/2018 19:00 16.5 6.0 1020.5 0 none Ardnamurchan 24/06/2018 23:35 12.6 4.7 1020.6 0 none Black Cuillins 25/06/2018 10:10 16.5 4.1 1022.6 6 none Muck 25/06/2018 15:45 20 10.8 1023.5 1 none Muck 25/06/2018 23:30 14.9 8.5 1023.2 1 none Rum 26/06/2018 15:00 19.3 4.5 1021.7 8 a few light spots Ardnamurchan 26/06/2018 22:55 20.0 4.1 1021.2 0 none Black Cuillins 27/06/2018 09:15 24.5 3.2 1022.3 0 none Black Cuillins 27/06/2018 14:30 28.0 8.5 1022.1 0 none Ardnamurchan 27/06/2018 19:00 26.1 4.7 1021.6 0 none Ardnamurchan 27/06/2018 23:10 16.8 9.4 1022.2 0 none Black Cuillins 28/06/2018 10:50 23.3 6.5 1023.5 0 none Black Cuillins 28/06/2018 15:50 25.5 6.2 1023.0 0 none Black Cuillins 28/06/2018 23:00 16.0 9.8 1022.5 0 none Black Cuillins 29/06/2018 13:35 19.3 8.2 1019.7 0 none Rum 29/06/2018 23:00 18.0 1.9 1016.5 0 none Biod Mor 30/06/2018 11:10 20.6 20.5 1013.3 0 none Rum

Figure 1. Visibility was measured in relation to several prominent landforms visible from ‘the village’ on the north side of Lunga.

Chris Heward

TIARG Annual Report 2018 v06/01/19 6

Systematic list of birds for 2018

The following systematic list describes those bird species seen during the Treshnish Isles Auk Ringing Group’s (TIARG) presence on the Treshnish Isles, 23rd – 30th June 2018. The introductory comments (first paragraph) refer to the species’ status during the breeding season as recorded by previous expeditions.

A detailed breakdown of breeding seabird numbers on the Treshnish Isles in 2018 is provided on page 21.

Canada Goose Branta canadensis Rare visitor. Four adult birds were seen on Sgeir an Eirionnaich on 27th and 28th June. The first record of the species breeding on the Treshnish Isles was confirmed by TIARG on Bac Mór where two adults and two goslings were seen during a visit on 28th June. These sightings represent the third and fourth records by TIARG of the species on the Treshnish Isles, the previous records in 2016 and 2017.

Greylag Goose Anser anser Breeding noted in some years, with a moulting flock present during late summer. The moult flock centred north of Lunga had built up to at least 198 birds by 26th June, typically most were around the islands of Sgeir an Eirionnaich, Fladda and Sgeir an Fheòir. At least an additional 86 were seen on Bac Mór during a survey from sea and land of Bac Mór and Bac Beag on 28th June. Well grown broods were associated with both moult flocks. Tabulated below are the annual peak counts of the moult flock centred north of Lunga.

Year 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Peak 25 160 240 268 79 101 316 90 164 77 80 count Year 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Peak 225 160 140 50 140 196 272 70 98 198 count

One of the birds seen on Bac Mór on 28th June was a neck collared with the code NCX. This bird was originally ringed at Cornabus, Islay, Argyll, on 16th November 2017 where it was re-sighted on the 7th February and 16th March 2018.

Shelduck Tadorna tadorna Until recently a rare visitor with one pair having bred occasionally since 2003. Two birds were seen off the north end of Lunga on 26th June.

Teal Anas crecca Rare visitor A pair of adults was seen on Bac Mór during a visit by TIARG on 28th June. This sighting represents only the second by TIARG of the species on the Treshnish Isles, the previous record in 1993 when one was flushed from Little Dutchman (Walker & Cooper 1986).

Eider Somateria mollissima Breeds regularly in small numbers. Three broods were noted at North Haven, Fladda on 29th June, with single ducks accompanying two, three and four ducklings respectively. Elsewhere a duck with one duckling were seen on Lunga and a duck with four ducklings seen at Cairn na Burgh Beag. The waters between Fladda and Lunga supported small numbers of late-summer moulting birds, typically male-biased with a minimum of 21 birds on 27th June. A single bird was noted at during a brief visit to Bac Mór on 28th June.

Storm Petrel Hydrobates pelagicus A common breeding species. The Treshnish Isles supported 20% of the Great Britain population and between 0.7 – 1.7% of the Atlantic (north-eastern) population as estimated by Seabird 2000. In July, a complete census of Lunga, Sgeir a Chaisteil and Fladda estimated a breeding population of 3,251, 262 and 5,151 apparently occupied nest sites. It is known from the only complete census in 1996, that breeding birds were also present on Bac Mór, Bac Beag, Cairn na Burgh More and Cairn na Burgh Beg,

TIARG Annual Report 2018 v06/01/19 7

totalling an estimated 18% of the total population for the Treshnish Isles. A full account of this survey by TIARG is reported elsewhere (tiarg.org). During the day in late June, one bird was found at the entrance to a nesting burrow, a second on the ground in Area 10 and a third dead not predated on Fladda. Four nights of light winds and no rain gave the opportunity in late June to mist net for Storm Petrels on Lunga at the Village and the Boulder Beach. On the Boulder Beach, traditionally ringed localities near the Well and below the Village on single nights, provided catches of 215 and 206 birds using two 18 m (for 2½ hours), and one 12 m net (1¾ hours) respectively. At the Village, 131 birds were caught using three 18 m nets over two nights (for 5 hours 25 mins period in total).

Fulmar Fulmarus glacialis A common breeding species. The Treshnish Isles supported 0.2% of the Great Britain population as estimated by Seabird 2000. Breeding was confirmed on Lunga, Bac Mór, Bac Beag, Cairn na Burgh Beg, Cairn na Burgh More, Fladda and Sgeir a’ Chaisteil. The breeding population for Lunga and Sgeir a’ Chaisteil was estimated at 245 pairs based upon apparently occupied sites (AOS). This represents a 9% decline in the number of breeding birds from the previous year. Over the longer term, 1994-2018, the population has shown an overall decline. This is consistent with a decline nationally which may be due to declines in offal from trawlers, representing a ‘re-adjustment’ to more natural levels following a period of artificially elevated population size (JNCC 2016). The estimated breeding population on the Treshnish Isles was 335 AOSs, a 69% reduction from the 1,078 INDs counted by Seabird 2000 in 1999.

Manx Shearwater Puffinus puffinus A common breeding species. The Treshnish Isles supported 0.4% of the Great Britain population as estimated by Seabird 2000 (1998 – 2002). In May, a complete census of Lunga by TIARG estimated a breeding population of 1,992 pairs based upon AOSs. This is a 55% increase from the previous population estimate of 1,283 pairs in 2000 (Offer 2000). Very few if any breeding birds were considered to occupy the other islands, as little or no suitable habitat exists. A full account of this survey is reported elsewhere (tiarg.org). Presumed breeding birds were seen and heard at night on Lunga by the expedition in late June. Small numbers of birds were seen daily, feeding or passing offshore of Lunga. During the week in the evenings up to 1,000 birds were noted rafting off the east coast of Lunga.

Grey Heron Ardea cinerea Rare visitor. Four birds were seen flying over the north end of Lunga heading west on 26th June. One bird was heard calling from Corran Lunga on 28th June.

Shag Phalacrocorax aristotelis A common breeding species. The Treshnish Isles supported 2.1% of the Great Britain population and between 0.8 – 0.9% of the Atlantic (northeastern) population as estimated by Seabird 2000 (1998 – 2002). Breeding was confirmed on Bac Mór, Bac Beag, Fladda, Lunga and Sgeir a Chaisteil. The estimated breeding population on the Treshnish Isles was 1,342 Apparently Occupied Nests (AON), a 123% increase from the 601 AONs counted by Seabird 2000 in 1999. Some change in the breeding distribution of birds has accompanied the population size increase, with a loss of birds from the smaller breeding populations on Cairn na Burgh More, Cairn na Burgh Beg and Sgeir an Eirionnaich, and reductions in the numbers of birds breeding on Bac Mór, Bac Beag, Lunga and Sgeir a Chaisteil (see a detailed breakdown of breeding seabird numbers on the Treshnish Isles in 2018 is provided on page 21). Those losses have been more than equally compensated for by a 387% population increase in the population of birds breeding on Fladda since 1999, with 1,081 AONs counted where previously there were 222 nests. The cause of this significant population increase and marked re-distribution is unknown. The population dynamics over the intervening years is unknown for most of the islands. Where it has been followed annually, on Lunga and Sgeir a Chaisteil, following a marked decline in the numbers of active nests in 2005 and 2006, numbers have since gradually increased with fluctuations from 78 to 244 active nests; in 1999, the total for the two islands was 295. A major difficulty associated with a breeding census of this species is its prolonged and variable breeding season (eggs have been laid in every month of the year except September and October in the U.K.). Additionally, in occasional years many adults do not breed (JNCC 2016). The former problem is overcome by conducting a single count in the period of maximum nest occupancy (May - June). It is

TIARG Annual Report 2018 v06/01/19 8

inevitable however that these problems will have led to an underestimate of the absolute size of the breeding population on the Treshnish Isles with empty nests noted in most years and fledged young in some years by TIARG. In 2018, of those birds that were breeding on Lunga and Sgeir a’ Chaisteil, great variation was once again found in the progress of breeding, with all stages from eggs to already fledged young noted. Overall breeding was not as advanced as an average year, with most nests containing eggs or young chicks. Brood sizes were mostly small, typically only two or three young. Large numbers of adults were in the vicinity of the colonies with over 500 birds moving offshore from the islands in the mornings to forage. 2018 was the thirteenth year of a Retrap Adult Survival study (RAS) that entails ringing each adult with its own uniquely engraved colour-ring so that it can be identified in the field in future years. This is part of the BTO’s Integrated Population Monitoring Programme funded by the UK Government (http://www.bto.org/ringing/ringinfo/ras/index.htm). In 2018, of the birds marked from 2006 to 2017 on Lunga, 64 out of a possible 351 individuals were re-sighted and/or recaptured by TIARG in June. A further 33 breeding adults were colour-ringed on Lunga in 2018. In May (26th May – 1 June), an additional seven birds were re-sighted by TIARG on Lunga.

Gannet Morus bassanus Regularly seen offshore Small numbers of adult birds were seen daily, feeding or passing offshore of Lunga. The largest count was of 22 adults on the sea west of Lunga.

White-tailed Eagle Haliaeetus albicilla Rare visitor There were no records of this species during the expedition.

Buzzard Buteo buteo Until recently, one pair bred in most years. Regular sightings suggested the presence of one pair of adults on Lunga, both birds being in active wing moult. Presumably the same pair were seen displaying over Sgeir a’ Chaisteil on 30th June. A juvenile was also seen on two occasions over Sgeir a’ Chaisteil, accompanied once by an adult. One adult bird was seen to be mobbed by a Great Skua over Fladda on 29th June.

Water Rail Rallus aquaticus Rare visitor. One bird was heard calling on 25th June from a bracken covered cliff top area immediately east of the Village. This was in the same locality as single birds have been recorded in the previous four years, prior to which the species had not been recorded by TIARG. A second bird was heard calling from the reedbed at the south end of Lunga on 25th June.

Corncrake Crex crex Recorded almost annually and probably a regular breeder in small numbers. Single males were regularly seen and heard calling from the vicinity of the Village and above the second gully on the east coast of Lunga. On one occasion, a single male was heard calling on Corran Lunga, Lunga. A female was also regularly heard calling from the vicinity of the Village, Lunga, a recording of which has been uploaded to www.xeno-canto.org/423731 (Shaun Micklewright). The identity and sex of this latter bird was confirmed following research on the internet e.g. https://soundcloud.com/klasse- 1/bothbirdseqnorm and Ottvall (1999). One male was heard calling during a brief visit to Bac Mór on 28th June.

Oystercatcher Haematopus ostralegus Breeds regularly in small numbers. A total of 28 breeding pairs were noted as follows. On Lunga’s beaches and rocky outcrops, seven pairs (two pairs at Corran Lunga and single pairs in areas 2, 4, 5, 6a and 8) were behaving as though on breeding territory, alarming at human intruders and performing displays on the appearance of other Oystercatchers. Away from Lunga, breeding pairs held territories on Cairn na Burgh More (two pairs), Cairn na Burgh Beg (two pairs), Bac Mór (two pairs with young), Bac Beg (three pairs), Fladda (five pairs), Sgeir an Eirionnaich (three pairs), Sgeir a’ Chaisteil (two pairs), Sgeir an Fheòir (one pair) and Sgeirean na Giusaich (one pair with young). Small flocks of presumed failed/non-breeders were evident on Lunga, typically at high tide, in the area of Sgeir a’ Chaisteil and Corran Lunga where there would generally be up to 25 birds roosting.

TIARG Annual Report 2018 v06/01/19 9

Ringed Plover Charadrius hiaticula One or two pairs breed annually. Typically, the only breeding pair on Lunga was confined to Corran Lunga, where one pair with a chick was present. One pair alarmed at human intruders during a brief visit to Sgeir a’ Chaisteil on 25th June. Elsewhere during brief visits to Fladda and Sgeir na h-lolaire, three and one breeding pairs respectively were noted with birds behaving as though on breeding territory and alarming at human intruders.

Curlew Numenius arquatus An irregular visitor. Six birds were seen flying north from the north end of Lunga on the 23rd June. Single birds were also seen from the north end of Lunga on the 28th and 29th June.

Dunlin Calidris alpina An irregular visitor. A single bird, a female C.a.schinzii, was seen during a brief visit to Sgeir an Fheòir the 29th June. A flock of 7 birds were also seen on the Boulder Beach, Lunga, on 30th June.

Common Sandpiper Actitis hypoleucos One or two pairs usually breed. No evidence of breeding was noted on Lunga, with single birds noted on occasions at Corran Lunga. One pair alarmed at human intruders during a brief visit to Sgeir a’ Chaisteil on 25th June.

Redshank Tringa totanus Irregular visitor A single bird was heard from the Boulder Beach, Lunga in the early morning of 28th June.

Snipe Gallinago gallinago Breeds regularly in small numbers. Up to three birds could be heard drumming/chipping over the Village on most days. One adult flushed from young chicks at Shearwater Gully. Elsewhere on Lunga, up to two birds could be heard drumming/chipping between Shearwater Gully and Shag Alley (Area 3), one bird chipping on Corran Lunga and single birds were flushed in Area 6 and 12. Elsewhere during brief visits to the other Treshnish Isles, a total of three birds were heard drumming on Fladda, two birds were seen on Cairn na Burgh Beag, three on Bac Beag and singles on Bac Mór, Sgeir an Eirionnaich and Cairn Burgh More.

Kittiwake Rissa tridactyla A localised breeding species. The Treshnish Isles supported 0.2% of the Great Britain population as estimated by Seabird 2000 (1998 – 2002). Breeding was confirmed only on Lunga, where the main colony is around Harp Rock. The number of apparently occupied nests on Lunga was 522. A marked population decline of the colony from 2008 ended in 2011 since when numbers have widely fluctuated. The breeding season was considered no more or less advanced than average for this species. Up to 345 birds were dispersed between roosts on Sgeir an Eirionnaich and the intertidal rocks off Sgeir a’ Chaisteil. Amongst these birds were several first-summer individuals. The estimated breeding population on the Treshnish Isles was 522 AONs, a 34% decrease from the 786 AONs counted by Seabird 2000 in 1999.

Common Gull Larus canus Regular? breeding species in small numbers. Five pairs were estimated to be holding breeding territories on Fladda, found during a visit by TIARG on 29th June; 4 pairs (seven birds counted) on the low-lying basalt rock outcrop on Fladda’s south-east coast and a pair (two birds counted) on the east side of North Haven. Up to eight adult birds were seen on occasions in the vicinity of Corran Lunga, Lunga, with also a first-summer and second-summer bird noted on single dates. No birds were found to be occupying territories elsewhere in the Treshnish Isles. The estimated breeding population on the Treshnish Isles was five pairs, a 38% decrease from the eight pairs counted by Seabird 2000 in 1999.

TIARG Annual Report 2018 v06/01/19 10

Great Black-backed Gull Larus marinus A regular breeding species. The Treshnish Isles supported 2.0% of the Great Britain population as estimated by Seabird 2000 (1998 – 2002). From colony visits, breeding was confirmed on Lunga (eight pairs), Sgeir an Eirionnaich (estimated six apparently occupied territories; up to 12 adults counted with five young found), Sgeir an Fheòir (five pairs), Sgeir na h-lolaire (one pair), Fladda (estimated 28 pairs; 56 adults counted when flushed), Bac Mór (14 pairs; a minimum of eight pairs with chicks), Bac Beag (six apparently occupied territories; 12 adults counted when flushed), Cairn na Burgh More (one pair) and Cairn na Burgh Beg (two pairs). No birds were occupying territories on Sgeirean na Guisaich or Sgeir a’ Chaisteil. The breeding season was considered no more or less advanced than average for this species. The small numbers of birds now breeding on Lunga follows a marked decline in population during the early 2000’s (see section “Population changes for a selection of breeding species on Lunga, 1994 – 2014”). The estimated breeding population on the Treshnish Isles was 53 pairs, a 85% reduction from the 342 pairs counted by Seabird 2000 in 1999.

Herring Gull Larus argentatus A regular breeding species. The Treshnish Isles supported 0.2% of the Great Britain population as estimated by Seabird 2000 (1998 – 2002). Breeding was confirmed on Lunga (estimated four pairs, eight adults counted when flushed; two nests) within gullery at the south end of Lunga, in area 8. Breeding was also confirmed on Fladda (estimated six apparently occupied territories; up to 15 adults counted), Bac Mór (estimated four pairs, eight adults counted when flushed) and Cairn na Burgh More (estimated six pairs). No birds were found to be occupying territories elsewhere in the Treshnish Isles. The small number of birds now breeding on Lunga follows a marked decline in population during the late 1990s / early 2000s (see section “Population changes for a selection of breeding species on Lunga, 1994 – 2016”). The estimated breeding population on the Treshnish Isles was 19 pairs, a 92% reduction from the 225 pairs counted by Seabird 2000 in 1999.

Lesser Black-backed Gull Larus fuscus Regular breeding species in small numbers. One apparently occupied territory was noted within the gullery at the south end of Lunga, in area 8. Elsewhere an estimated five pairs (10 birds counted when flushed) were found on Fladda and one pair on Bac Mór during brief visits by TIARG. No birds were found to be occupying territories elsewhere in the Treshnish Isles. The estimated breeding population on the Treshnish Isles was seven pairs, an 83% reduction from the 40 pairs counted by Seabird 2000 in 1999.

Common Tern Sterna hirundo Irregular breeding species. The Treshnish Isles supported 0.6% of the Great Britain population as estimated by Seabird 2000 (1998 – 2002). The behaviour of two adults on Sgeir an Eirionnaich towards avian predators suggested that they were incubating eggs or had very young chicks on the 29th June. An estimated 50 adults were counted amongst 450 mixed Arctic and Common Terns when flushed at a ternery on Sgeirean na Giusaich. On the assumption that the number of nests counted in the mixed ternery is for each species proportionate to the number of adult birds recorded in the flush count, 16 nests are attributable to Common Tern. No individuals of this species were identified amongst the terns flushed on Sgeir na h-lolaire. The estimated breeding population on the Treshnish Isles was 17 pairs, a 180% increase from the 6 pairs counted by Seabird 2000 in 1999.

Arctic Tern Sterna paradisaea Regular breeding species. Terneries were present on Sgeir an Eirionnaich, Sgeirean na Giusaich and Sgeir na h-lolaire. Tabulated below are from each site counts of Arctic/Common Terns nests and the estimated number of Arctic Terns flushed during brief census visits on 28th June. On the assumption that the number of nests counted on Sgeirean na Giusaich in the mixed ternery is for each species proportionate to the number of adult birds recorded in the flush count (a ratio of 1:8 based on 50 Common Terns and 400 Arctic Terns flushed), 127 nests are attributable to Arctic Tern. The estimated breeding population on the Treshnish Isles was 127 pairs, a 18% reduction from the

TIARG Annual Report 2018 v06/01/19 11

154 pairs counted by Seabird 2000 in 1999. In making such a comparison it should however be noted that in unlike other seabirds, populations of breeding terns can be very mobile, with part or all of a colony shifting location between years to another colony.

Site Nest counts of Arctic/Common Terns Estimated no. Empty 1 egg 2 eggs 3 eggs Total no. of Chicks of Arctic Terns nest nests in flush count of ternery Sgeirean na Giusaich 0 41 64 23 143 13 400 Sgeir an Eirionnaich 0 0 7 0 7 0 70 Sgeir na h-lolaire 4 4 19 5 32 0 120

Great Skua Stercorarius skua A small but regular breeding population has become established since the first confirmed breeding by a pair in 1998. On Lunga, where up to four birds were noted daily, no breeding territories were found. Breeding was confirmed on Bac Mór (estimated three apparently occupied territories with one egg in a nest and a chick in separate territories) and Fladda (estimated four apparently occupied territories with one nest containing two eggs in one territory). Birds were seen to predate adult birds of Shag, Common Gull and Great Black-backed Gulls. Attacks were also seen on more than one occasion on moulting Greylag Geese.

Arctic Skua Stercorarius parasiticus Small numbers seen daily, presumably from the breeding grounds on Coll. Up to three birds, two dark phase and a single light phase, were recorded almost daily from Lunga. On two occasions, the trio of birds were seen from the Village, Lunga, displaying.

Guillemot Uria aalge Common breeding species. The Treshnish Isles supported 0.7% of the Great Britain population as estimated by Seabird 2000 (1998 – 2002). Breeding was confirmed only on Lunga and Sgeir a’ Chaisteil and Fladda, with the main concentration as usual within the vicinity of Harp Rock where 9,941 adults were estimated. The total for Lunga and Sgeir a’ Chaisteil combined was 10,495. The mean count for the past five years is 8,302 birds (range 6,434-10,495). The breeding season was considered no more or less advanced than average for this species. The estimated breeding population on the Treshnish Isles was 10,495 individuals, a 10% increase from the 9,566 individuals counted by Seabird 2000 in 1999. Twenty adult birds known to be brooding chicks were caught at the colony and fitted with a geolocator attached to a ring that was put onto one of the birds’ legs. The aim is to catch the same individuals again one or two years later to recover the tag and download data on their daily locations between breeding seasons. From the data, a PhD student (TIARG member Lila Buckingham) will analyse the migration routes and wintering areas used by birds together with those from different breeding colonies around Scotland and north-east England. This study (managed by MacArthur Green, funded by Vattenfall) aims to provide detailed and accurate data on the year-round movements of adult guillemots and razorbills, with particular reference to populations likely to interact at some stage of the year with offshore wind farms in the North Sea.

Razorbill Alca torda Common breeding species. The Treshnish Isles supported 0.8% of the Great Britain population as estimated by Seabird 2000 (1998 – 2002). Breeding was confirmed on Lunga, Sgeir a’ Chaisteil, Cairn na Burgh Beg and Fladda. The main concentration was typically located within the vicinity of Harp Rock. A total of 580 birds was counted on Lunga and Sgeir a’ Chaisteil, in addition to the birds associated with 17 chicks located amongst accessible boulder colonies. The breeding season was considered no more or less advanced than average for this species. The estimated breeding population on the Treshnish Isles was 673 individuals, a 45% reduction from the 1,232 individuals counted by Seabird 2000 in 1999. Counts of apparently occupied nests have been converted into an approximate estimate of the number of individuals to be seen at a colony at any one time by dividing by a correction factor 0.67 to allow for the presence of non-breeders and the attendance of

TIARG Annual Report 2018 v06/01/19 12

breeding birds. This correction factor has been shown to be generally representative in Britain (Harris et al. 2015). Twenty adult birds known to be brooding chicks, where caught at the colonies at Harp Rock and the Boulder Beach, Lunga, and were fitted with a geolocator attached to a ring that was put onto one of the birds’ legs (see Guillemot for further details).

Black Guillemot Cepphus grylle Regular breeding species in small numbers. The Treshnish Isles supported 0.4% of the Great Britain population as estimated by Seabird 2000 (1998 – 2002). Adults were seen around Sgeir an Eirionnaich (one bird), Fladda (21), Bac Mór (eight), Bac Beag (five), Cairn na Burgh More (ten) and Lunga (eight). Breeding was confirmed on Lunga, Bac Mór and Fladda where birds were noted exiting nest sites. The estimated breeding population on the Treshnish Isles was 54 individuals, a 33% reduction from the 70 individuals counted by Seabird 2000 in 1999 (when a correction factor was used by TIARG of one bird counted equated to one breeding pair).

Puffin Fratercula arctica Common breeding species. The Treshnish Isles supported 0.3% of the Great Britain population as estimated by Seabird 2000 (1998 – 2002). Breeding adults occupied burrows on Lunga, Sgeir a’ Chaisteil, Bac Mór, Cairn na Burgh Beg and Fladda. Four adults were also seen in suitable breeding habitat on an inaccessible cliff on Bac Beag. The estimated breeding population on Lunga and Sgeir a’ Chaisteil was 2,441 apparently occupied burrows (AOBs). For counts of birds, one bird is taken to represent one AOB (Mitchell et al. 2004). Numbers have since 2004 fluctuated between 2,423 and 3,349 AOBs with the exception of the comparatively low estimates of the two years 2010-2011; 1,705 and 1,611 AOBs respectively. One breeding plumaged adult was seen to unusually have no breeding plumage eye ornaments. The estimated breeding population on the Treshnish Isles was 2,583 AOBs, a 45% increase from the 1,788 AOBs counted by Seabird 2000 in 1999.

Rock Dove Columba livia Regular breeding species in very small numbers. Birds were seen daily on Lunga, principally along the east coast, the largest groups being of three adults with two fledged young. The young had fledged from a cave in Shag Alley where there were two other nests, containing two chicks and two eggs respectively. An abandoned nest with two eggs was found in the Blowhole (Area 7). During brief visits to the other islands, birds were seen on Cairn na Burgh More (three birds), and singles at birds), Cairn na Burgh Beg, Fladda and Bac Mór

Swift Apus apus Irregular visitor Between one and eight birds were seen or heard on three dates over Lunga.

Peregrine Falco peregrinus Seen most years with breeding known to occur on adjacent coasts. A single male bird in wing moult, was seen over Harp Rock, Lunga, on 28th June.

Hooded Crow Corvus cornix A regular breeding bird in small numbers. The species was seen daily either on or flying between Lunga and Sgeir a’ Chaisteil, with no more than three adults noted at any one time. Sightings would suggest the presence of no more than single pairs on Sgeir a’ Chaisteil and the south end of Lunga. Elsewhere during brief visits to adjacent islands, one bird was seen on Bac Beg, two adults with two fledged young on Cairn na Burgh Beg and 2 birds on Fladda. A corpse was also found on Fladda; cause of death unknown.

Raven Corvus corax At least one pair breeds in most years. Up to seven individuals were seen on occasions frequenting Lunga. At least two birds were moulting adults that were accompanied at times by what were thought to be five juveniles due to the absence of wing moult or abraded flight feathers. Elsewhere during brief visits to adjacent islands, four presumed juvenile birds (absence of wing

TIARG Annual Report 2018 v06/01/19 13

moult) were seen on Cairn na Burgh Beg.

Skylark Alauda arvensis A regular breeding species in small numbers. Up to five singing males were on Lunga. Single singing males were present on the slope of Cruachan above Shag Alley, at the Village and south of Tarbet in Area 6. A further two singing birds were noted in Area 7. Two birds were flushed in Area 6 and another in Area 7 on 30th June. A single bird was heard to call when over flying the Village, Lunga, on 25th June. Elsewhere during brief visits to the Treshnish Isles other islands, the species was not recorded.

Swallow Hirundo rustica Irregular visitor Single birds were noted over the Village and South End, Lunga, on the 27th June. Elsewhere a bird was seen over Fladda on 29th June.

Sedge Warbler Acrocephalus schoenobaenus A scarce but almost annual visitor. One bird carrying food was seen in the reedbed at the south end of Lunga on 25th June.

Whitethroat Sylvia communis Rare visitor. One bird was located alarming between South and North Haven, Fladda.

Wren Troglodytes troglodytes A regular breeding species, quite common where habitat is suitable. As in previous years, the vast majority of records were confined to the northern half of Lunga, predominantly amongst the boulder scree and bracken-covered slopes from Cruachan down to the sea and on Corran Lunga. Food carrying, alarms, a nest and recently fledged young confirmed breeding on Lunga. There was a minimum of 7 territories recorded between the Village and Harp Rock. Elsewhere during brief visits to the Treshnish Isles other islands, the species was recorded on Fladda and Bac Mór (3 birds).

Treecreeper Certhia familiaris Rare visitor During a brief visit to Bac Mór on 28th June, a bird was seen foraging over lichen covered cliff. This is the first sighting recorded by TIARG of this unexpected species on these treeless islands.

Starling Sturnus vulgaris A regular breeding species in small numbers. Small flocks of up to 65 birds were noted daily on Lunga, comprising mostly of juveniles. Breeding was confirmed with a nest noted in Area 6a. Elsewhere during brief visits to the other islands, the species was recorded on Fladda (four birds), Cairn na Burgh Beg (one) and Bac Mór (three). An active nest was located on Cairn na Burgh More.

Song Thrush Turdus philomelos Rare visitor One bird was seen in the Village, Lunga, on 24th June.

Wheatear Oenanthe oenanthe A regular breeding species in small numbers. Widespread breeding species on Lunga with adults and fledged young observed across all count areas. Elsewhere during brief visits to the Treshnish Isles other islands, birds were seen on Bac Mór (3 birds), Bac Beag (2), Sgeir an Eirionnaich (2) and Fladda.

Dunnock Prunella modularis Irregular breeding species. A singing male was heard daily near the Village.

TIARG Annual Report 2018 v06/01/19 14

Pied Wagtail Motacilla alba yarrelli A regular breeding species in very small numbers. One pair of adults were regularly seen in the vicinity of the Village, Lunga. Nearby, two adults and five juveniles were seen at the Puffin Terraces, Lunga, on 29th June. In the vicinity of Harp Rock, up to two juveniles and an adult were seen on occasions. Single record occurrences elsewhere on Lunga included an adult at Shag Alley and a single bird on Corran Lunga. Elsewhere during brief visits to the other islands, the only record was of a juvenile seen between the Havens on Fladda.

Meadow Pipit Anthus pratensis A regular breeding species in small numbers. Widespread breeding species on Lunga with no estimate of territories made, though less numerous than Rock Pipit Anthus petrosus. Food carrying, alarms and recently fledged young confirmed breeding on Lunga. Elsewhere during brief visits to the Treshnish Isles other islands, the only records were of presumed breeders on Fladda and Bac Mór (14 birds).

Rock Pipit Anthus petrosus A regular breeding species in small numbers. Breeding birds were common along the coast of Lunga and on Sgeir a’ Chaisteil. Food carrying, alarms and recently fledged young confirmed breeding on Lunga and Sgeir a’ Chaisteil. Elsewhere during brief visits to the other islands the species was recorded on Fladda, Sgeir an Eirionnaich (four birds with one carrying food), Sgeir na h-lolaire (two), Cairn na Burgh Beag (ten), Bac Beg (one) and Bac Mór (13).

Twite Linaria flavirostris Regular breeding species in small numbers Small parties of up to three birds, including two adults with a juvenile, were noted daily around the northern half of Lunga. Elsewhere during brief visits to the other islands, the species was recorded on Fladda (including a single flock of 10+ birds), Cairn na Burgh Beag (seven), Bac Beg (one) and Bac Mór (parties of two and six birds).

Linnet Linaria cannabina Rare visitor A male was seen at the Well, Lunga, on 27th June.

A juvenile Wheatear (Andrew Carter)

TIARG Annual Report 2018 v06/01/19 15

Systematic list of mammals for 2018

Otter Lutra lutra Evidence of presence regularly noted. However, in this year, no evidence of this species was noted on Lunga or during brief visits to any of the other Treshnish Isles during the expedition.

American Mink Neovison vison No known occurrences. No evidence of this species was noted on Lunga or during brief visits to any of the other Treshnish Isles during the expedition.

House Mouse Mus musculus Resident, apparently in small numbers. Individual animals were seen on several occasions at the expedition base in the Village, at the north end of Lunga. Chocolate wax monitoring blocks are a method with which to attract and record the distinctive bite marks of different rodent groups e.g. mice and rats (Varnham 2008). Pairs of chocolate wax monitoring blocks, “chew sticks”, were laid for two successive days overnight at four locations at the east end of the settlement at the southern foot of Cruachan, Lunga (amongst the remaining wall foundations of a house), and east of this settlement at ten locations with a field boundary wall. Chew sticks were later laid for two successive days overnight at ten locations within the southern end of the seabird boulder colony in Area 10. The chew sticks were then inspected for rodent teeth marks. The chocolate wax monitoring blocks were made following the method of Varnham (2008). No rodents were detected at any of the localities that chew sticks were deployed. No evidence of this species was noted during brief visits to any of the other Treshnish Isles.

Brown Rat Rattus norvegicus No known occurrences. No evidence of this species was noted on Lunga or during brief visits to any of the other Treshnish Isles during the expedition.

Rabbit Oryctolagus cuniculus Resident, numbers much reduced in recent years. No systematic monitoring took place. Casual observations on Lunga suggest a marked reduction in the number of animals on Lunga compared with the most recent years. No more than six animals were recorded daily from widespread localities. One black individual was seen north of Tarbet, Lunga. No evidence was noted of animals on any of the other islands of the Treshnish Isles during the brief visits by TIARG.

Grey Seal Halichoerus grypus A regular breeding species, contributing just under 3% of the annual UK pup production. Numbers are regularly monitored by the Sea Mammal Research Unit (NERC, St Andrews). The conservation importance of these islands as a breeding colony is recognised by their designation by the UK Government as a Special Area of Conservation. A maximum of 156 animals were visible from Lunga hauled out on intertidal reefs to the north and east at low tide. At the south end of Tarbet off Area 5, up to 13 animals were hauled out on intertidal rock on 24th June. Elsewhere 32 animals were seen during brief visits to Bac Beg, seven at Bac Mór, 27 at the Cairn na Burghs and 12 at Fladda.

Harbour Porpoise Phocoena phocoena Rare visitor. Two animals were seen off the west coast of Lunga on 25th June. Two separate groups of two adults and a calf, and five more animals were watched in quick succession when TIARG were crossing between Lunga and Bac Mór on 28th June.

Pipistrelle Bat Pipistrellus pipistrellus (45 kHz) Previously regarded a rare visitor. True status uncertain. Single animals of this species, now recorded annually since 2011, were noted over the Village on two nights. The identity was confirmed by the use of a bat detector.

TIARG Annual Report 2018 v06/01/19 16

Systematic list of lepidoptera for 2018

Common Blue Polyommatus icarus Regular breeder Up to 50+ were recorded daily on Lunga. Elsewhere during brief visits to the other islands, the species was recorded on Fladda (15 on 29th June), Sgeir an Eirionnaich, Cairn na Burgh More, Cairn na Burgh Beag, Bac Beg and Bac Mór.

Red Admiral Vanessa atalanta Migrant One or two individuals were recorded at the Village, Lunga, on three dates. Elsewhere during brief visits to the other islands, the species was recorded on Fladda (five), and singles on Sgeir an Fheòir, Sgeir na h-lolaire, Sgeir an Eirionnaich, Cairn na Burgh More and Cairn na Burgh Beag .

Painted Lady Vanessa cardui Regular migrant Up to six individuals were recorded on Lunga on four dates. Elsewhere the species was seen during brief visits to Sgeir an Eirionnaich, Cairn na Burgh Beag and Bac Mór.

Green-veined White Pieris napi Possible breeder A single was seen at the Village, Lunga on 27th June.

Dark Green Fritillary Argynnis aglaja Accidental A single was seen at Corran Lunga, Lunga on 24th June.

Ringlet Aphantopus hyperantus Possible breeder Up to two individuals were seen on four dates on Lunga.

Meadow Brown Maniola jurtina Possible breeder Up to five individuals were seen on five dates on Lunga. A single was seen on Fladda during a brief visit on 29th June.

Wall Brown Lasiommata megera Accidental One was seen along the west coast south of Harp Rock, Lunga (area 12) on 24th June.

Map-winged Swift Hepialus fusconebulosa One caught near the Village, Lunga, and another at the Village in a moth trap on 24th June, and two more in the moth trap on the 26th June.

Six-spot Burnet Zygaena filipendulae Commonly sighted across Lunga, particularly south of Harp Rock. 7+ sighted on 26th June.

Hummingbird Hawkmoth Macroglossum stellatarum One on Bac Mòr on 28th June.

Garden Tiger Arctia caia One seen on the 24th June on the walk down to Boulder Beach, Lunga.

Buff Ermine Spilosoma luteum Caught in a moth trap on 26th June near the Village, Lunga.

White Ermine Spilosoma lubricipeda One at the Village, Lunga, on 27th June.

TIARG Annual Report 2018 v06/01/19 17

Northern Dart Xestia alpicola Caught in moth trap at the Village, Lunga, on 26th June.

Bright-line Brown-eye Lacanobia oleracea Caught in moth trap at the Village, Lunga, on 25th June.

Small Angle Shades Euplexia lucipara Caught in moth trap at the Village, Lunga, on 24th June.

Dusky Brocade Apamea remissa Caught in moth trap at the Village, Lunga, on 25th June.

Silver Y Autographa gamma Multiple sightings on Lunga: 24th June on the walk down to Boulder Beach and 5+ around the Village on 26th June. Also present on Bac Beag on 28th June.

Nettle-tap Anthophila fabriciana One at the Village, Lunga, on 26th June.

Other notable wildlife records

Oyster Plant Mertensia maritima Localised species on Lunga. At Tarbet (west) the species continues to be well established with no marked difference in abundance and extent to that of recent years.

Red-tailed Bumblebee Bombus lapidarius A queen seen at the Village, Lunga, on 28th June.

White-tailed Bumblebee Bombus lucorum Seen on the Cairn na Burgh's.

Grey Earthworm Aporrectodea caliginosa One seen on Lunga.

Ground Beetle sp. Abax parallelepipedus Plentiful on Lunga.

Diving Beetle sp. Agabus bipustulatus Plentiful in pools at Tarbet, Lunga. Identified from an individual found on 26th June.

TIARG Annual Report 2018 v06/01/19 18

Six-spot Burnet Moths (Andrew Carter)

TIARG Annual Report 2018 v06/01/19 19

Map of census zones – Lunga and Sgeir a’ Chaisteil

TIARG Annual Report 2018 v06/01/19 20

Breeding seabird census data for the Treshnish Isles in 2018

Sector Count Lunga Sgeir a’ Sgeirean na Sgeir an Sgeir an Sgeir na Fladda Cairn na Cairn na Bac Mór Bac Beag Grand unit Chaisteil Giusaich Fheoir Eirionnaich h-lolaire Burgh Burgh Beg total: More Treshnish Isles Fulmar AOS 207 38 8 12 7 52 11 335 Manx Shearwater AOS 1,992 1,992 Storm Petrel AOS 3,251 262 5,151 * * * * 8,664+ Shag AON 238 6 1,083 13 2 1,342 Great Skua AOT 4 3 7 Lesser B-b Gull AOT 1** 5** 1 7 Herring Gull AOT 4** 6** 5 4** 19 Great B-b Gull AOT 8 5** 6** 1 10** 1 2 14** 6** 53 Common Gull AOT 5 5 Kittiwake AON 522 522 Common Tern IND 50$$ 2$$ 52 Arctic Tern IND 400$$ 70$$ 120$$ 590 Arctic/Common Tern AON 143 7 32 182 Razorbill IND 549 31 65 2 647 Razorbill AON 17 17 Razorbill SEA 70 25 70 Guillemot IND 10,316 179 10,495 Guillemot SEA 402 1 403 Black Guillemot IND 9 1 21 10 8 5 54 Puffin SEA 817 17 834 Puffin IND 289 74 4 367 Puffin AOB 1,850 302 1 47 16 2,216

Key to count unit codes: AON/AOT/AOB/AOS = apparently occupied nest/territory/burrow/site IND = Individuals on land SEA = individuals on sea within 200m of colony PRS = Pairs nc = no count + = breeders present **Estimated from flush counts with the number of adults divided by two $$ Flush counts of adults made during count of nests

TIARG Annual Report 2018 v06/01/19 21

Breeding seabird numbers for each census zone of Lunga and Sgeir a’ Chaisteil in 2018

Sector Count Count Sectors on Lunga (1 – 12a) and Sgeir a’ Chaisteil (13) Lunga & Chaisteil Unit 1 2 3 4 5 6 6a 7 8 9 10 11 12 12a 13 Totals Fulmar AOS 34 8 2 31 12 18 11 12 79 0 38 245 Shag AON 16 40 1 39 3 21 12 24 58 4 6 244 Great Skua AON 0 Lesser B-b Gull AOT 1 1 Herring Gull AOT 4 4 Great B-b Gull AOT 1 1 2 3 1 8 Kittiwake AON 491* 31 522 Razorbill IND 26 19 20 34 19 37 41 255 93 5 31 580 Razorbill AON 10 1 6 17 Razorbill SEA 4 12 54 70 Guillemot IND 17 1 102 9,941 255 179 10,495 Guillemot SEA 2 400 402 Black Guillemot IND 1 5 3 9 Puffin SEA 65 310 30 1 411 817 Puffin IND 10 22 25 242 289 Puffin AOB 36 136 674 1,004 302 2,152

Key to count unit codes: AON/AOT/AOB = apparently occupied nest/territory/burrow IND = Individuals on land SEA = individuals on sea within 200m of colony PRS = Pairs nc = no count + = breeders present * 78 birds were only visible when counted from the sea (35 AON) and a wave cut platform (43 AON). These were not in previous years accessible to view to include in the annual count unless otherwise stated.

TIARG Annual Report 2018 v06/01/19 22

Population changes for a selection of breeding species on Lunga, 1994 – 2018

GUILLEMOT 350 SHAG

10000 300 250 8000 200 6000 150 4000

No. of nestsof No. 100

No. ofindividuals No. 2000 50

0 0 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018

3500 PUFFIN RAZORBILL 2000 3000 2500 1600

2000 1200 1500 800 burrows 1000

500 ofindividuals No. 400

No. of apparently occupied occupied apparently of No. 0 0 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018

TIARG Annual Report 2018 v06/01/19 23

Population changes for a selection of breeding species on Lunga, 1994 – 2018 (con’t)

FULMAR 1000 KITTIWAKE 700 600 800 500 600 400 300

400 nests

No. of nests of No. 200 200 100

0 occupied apparently of No. 0 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018

HERRING GULL GREAT BLACK-BACKED GULL 100 80

80 60 60 40 40 territories territories 20 20 No. of apparently occupied apparently of No. 0 occupied apparently of No. 0 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 1994 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018

TIARG Annual Report 2018 v06/01/19 24

Treshnish ringing totals for 23 – 30th June 2018

Site Species New birds Recaptures Total Adult Juvenile Pulli Retraps Controls Lunga Manx Shearwater 2 3 5 Storm Petrel 426 110 16 552 Shag 24 101 80 205 Oystercatcher 1 1 Ringed Plover 1 1 Herring Gull 1 1 Kittiwake 11 9 20 Guillemot 327 43 1 371 Razorbill 65 12 1 78 Puffin 141 21 1 163 Wheatear 3 3 Rock Pipit 2 2 Wren 2 2

Bac Mor Greylag Goose 1 1 Great Skua 1 1

Fladda Herring Gull 1 1

Giusaich Arctic Tern 10 10

Sgeir an Eirionnaich Great Black-backed Gull 2 2 Arctic Tern 1 1

Treshnish Isles Grand total for 2018 1,003 119 278 20 1,420

*64 of 80 Shag ‘retraps’ were colour-ringed birds of which the majority were sighted and not captured. Note: All rings used in 2018 were registered to Treshnish Auk Ringing Group.

Manx Shearwater (Andrew Carter) TIARG Annual Report 2018 v06/01/19 25

Census of shags on Fladda, Treshnish Isles

Chris Heward1

1. Introduction

A complete census of breeding shags Phalacrocorax aristotelis was conducted on Fladda on 29th June 2018. This is two to three weeks later than the early June census period recommended by Walsh et al. (1995) but coincided with the wider seabird censuses that are conducted by TIARG each year. This means that our breeding population estimates ought to be considered minima but are likely to provide greater consistency with those of previous and future surveys.

2. Colonies

Fladda was divided into nine sectors using natural breaks that separate large aggregations of nesting shags. Figure 1 illustrates the approximate boundaries of these sectors.

3. Survey method and recommendations

The island was surveyed by a team of four people in around six hours. Each shag colony was censused in four ‘parallel’ transects with the uppermost surveyor following the base of the cliff, the lowermost surveyor just above the High Water Spring (HWS) level and the two remaining surveyors evenly spaced between them. All apparently occupied nests (AONs) were counted. The most efficient way of doing this was for the team to count aloud whilst walking through the colony; each surveyor calling out their contributions to the colony total as encountered. The lowermost surveyor recorded the group count as it progressed. With the start of each new colony the count began again at zero.

Walking four concurrent transects parallel with the tideline reduces the amount of lateral movement required from surveyors and helps prevent double counting. Even with this relatively efficient method, the survey is physically demanding and ought to not be attempted with a team / teams smaller than four people.

A small number of nests on the northern cliffs of Fladda cannot be accessed on foot. These were censused by boat.

4. Results

The numbers of AONs in each section are recorded in Table 1. The total number of AONs on Fladda was 1,081. This is approximately five times greater than the number of nests recorded on Lunga. It is also nearly five times larger than the last complete count of Fladda conducted as part of Seabird 2000 (AONs = 222) (TIARG 1999). Estimating the proportion of the UK population currently breeding on the Treshnish Isles is hindered by the lack of a recent national estimate but given the 1998-2002 estimate of 26,600 AONs (Mitchell et al. 2004) and the negative population trend recorded since 2000 (JNCC 2016), it is likely to be greater than 5%. It is likely that the Treshnish Isles now supports one of the largest, if not the largest, population of shags in the UK (see table 1 in JNCC 2016).

Nest stages ranged from unhatched eggs to well-developed chicks close to fledging. We found a small number of empty, soiled nests that probably suggest some chicks had already fledged prior to the survey (these nests are not included in our totals). This is supported by observations made during the late May 2018 expedition to survey Manx Shearwaters on Lunga when well grown young were noted.

Although most nests were sited under or between large boulders, as is typically seen on Lunga, we observed a greater variety of nest sites on Fladda. In very dense colonies, some nests were built in exposed locations on top of flat boulders and at the base of the cliffs Shags were found nesting amongst dense brambles and ivy. Densities were greatest below the western cliffs of Fladda and the boulders surrounding North and South Havens.

1 [email protected]

TIARG Annual Report 2018 v06/01/19 26

Table 1. Number of apparently occupied shag nests for each sector

Sector number Sector name Total no. of AONs A South Haven W 331 B Facing Lunga 136 C Facing Eirionnaich 136 D Dead End 54 E North Haven W 50 F North Haven E 174 G South Haven E + around the corner 111 H Common Gullery 48 I Facing Ulva 39 - North Coast (surveyed by boat) 2 TOTAL 1081

Figure 1. The ten sectors used to survey breeding shags on Fladda. Letters correspond to those provided in Table 1 and were counted on foot with the blue lined sectors surveyed by boat.

5. References

JNCC. 2016. European Shag Status and Trends. JNCC, Peterborough. Available online: http://jncc.defra.gov.uk/page-2877 [Accessed 2 September 2018]

TIARG Annual Report 2018 v06/01/19 27

Mitchell, P.I., Newton, S.F., Ratcliffe, N. and Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

TIARG. 1999. Treshnish Isles Auk Ringing Group Report for 1999. TIARG, UK.

Walsh, P.M., Halley, D.J., Harris, M.P., del Nevo, A., Sim, I.M.W., & Tasker, M.L. 1995. Seabird monitoring handbook for Britain and Ireland. JNCC / RSPB / ITE / Seabird Group, Peterborough.

Colour-ringed Shag ‘153’ (Andrew Carter)

TIARG Annual Report 2018 v06/01/19 28

Retrapping adults for survival project

1. Introduction

Breeding adult Storm Petrels and Shags are ringed annually by TIARG in specific sections of the colonies on Lunga. Since 2006 the conservation value of this aspect of TIARG’s ringing programme has been much increased by its inclusion into the British Trust for Ornithology’s Retrap Adult Survival (RAS) monitoring programme. Adult Shags are now fitted with a uniquely numbered colour ring; many of these birds have been metal ringed already as pulli by TIARG. Over 300 Shags are now individually identifiable in the field without the need for recapture. Adult Storm Petrels continue to be BTO metal ringed only.

2. What is RAS

RAS aims to provide information on adult survival. RAS uses re-sightings of colour-marked individuals and captures of adult birds to calculate what proportion survives each year. The aim of a RAS project is to re- recapture (or re-sight, Shag only), within a defined area, a minimum of 30 adult birds ringed in previous years. TIARG tries to avoid big changes in effort between years and keep a record of their catching effort (number of visits made and number of hours spent re-capturing and / or re-sighting). This means that survival can be calculated by the British Trust for Ornithology (BTO) more precisely from the information collected.

3. Study areas and Methods

3.1. Shag RAS

TIARG’s Shag RAS study areas extend along Lunga’s north-west coast and section of the east coast.

All adults are caught by hand in the colonies and usually at the nest. A single engraved darvic colour-ring is placed on the bird’s left leg. The colour-ring is either: 1) lime (light green) with a black engraved number between 100 to 299, read from top to bottom and repeated twice on the ring; or 2) dark green with a white engraved number between 300 to 499, read from top to bottom and repeated twice on the ring

During the annual one week visit to Lunga by TIARG at the end of June, expedition members record the details of any colour-ringed Shags seen, both during targeted searches of the colonies for marked birds, and at all other times.

3.2. Storm Petrel RAS

TIARG operate two Storm Petrel RASs on the north-east corner of Lunga. All adults are mist netted (without tape lure) in colonies. The study area of one RAS is the Village where a survey visit uses a line of three 18 m four shelf mist nets erected adjacent to the south side of the Cottages. The study area of the second RAS is the Boulder Beach. Here a survey visit comprises of using two or three 18 m nets positioned at the northern end or alternatively one 18 m or two 12 m nets towards the colony’s southern end (below the ‘latrine’).

During the annual one week visit to Lunga by TIARG at the end of June, expedition members attempt one night of mist netting at each of the three netting locations, or more if required to meet the sample of Storm Petrels required.

4. Results

The BTO has provided TIARG with project specific feedback on the results of the three RAS studies up to and including 2016. The results are presented here alongside the latest national trend for comparison. National survival trends are published as part of the BirdTrends report (www.bto.org/birdtrends) and on the RAS website (www.bto.org/ras-results).

TIARG Annual Report 2018 v06/01/19 29

4.1. Storm Petrel RAS

4.1.1. National trend TIARG’s RASs are two of three active projects for Storm Petrel in the UK, the other is on Priest Island, Highland. The national trend is generated from two historical and three current projects (Figure 1). The quality of the national trend is considered to be 'Good'. Following a prolonged, gradual decline, Storm Petrel survival rates exhibited a sharp increase in survival between 2013 and 2014 but declined again slightly between 2014 and 2015 before a second marked increase between 2016 and 2017.

Figure 1. The RAS programme national trend in the apparent adult survival of Storm Petrel

On viewing the graphs in this paper, the following three points should be noted:  That the graphs end at 2016; this is because the RAS programmes calculate survival between years, so the last point is the survival from 2016 to 2017.  The graphs show "Apparent Adult Survival", defined as the probability that an adult bird alive in the previous year survives and returns to the study area. The analysis accounts for the fact that birds which are present may not be seen every season, but birds permanently emigrating from the study area will be presumed dead, thus the true survival rate may be slightly higher than the figures presented here.  The dotted lines show the upper and lower 95% Confidence Limits around the average estimate (solid line and points). The closer these lines are to the solid line, the more confidence we have in the accuracy of the survival rates.

4.1.2. Boulder Beach RAS and The Village RAS The trend in the apparent adult survival at the TIARG’s two Storm Petrel RASs are shown in Figures 2 and 3. Interpretation of these trends are provided once in every three years by the British Trust for Ornithology, with the expectation of feedback in 2019.

TIARG Annual Report 2018 v06/01/19 30

Figure 2. The trend in the apparent adult survival of Storm Petrel at Boulder Beach RAS study

Figure 3. The trend in the apparent adult survival of Storm Petrel at the Village RAS study

TIARG Annual Report 2018 v06/01/19 31

A summary of the results for the TIARG Storm Petrel RAS studies are presented in Table 1. On viewing the summary results tabulations, the following three points should be noted:  The ‘mean survival rate’ is the probability that an individual bird alive in one breeding season will survive to the next averaged across all years and sites; and,  The ‘mean re-encounter rate’ is the probability that an individual (which is alive and living in the study area) will be either recaught or resighted.

Table 1: Summary results for the two Storm Petrel RAS studies

Boulder Beach RAS The Village RAS Estimate of average annual adult survival across all projects 78% 78% Estimate of average annual adult survival from TIARG project 81% 82% Estimate of TIARG project’s average annual recapture probability 8% 17%

4.2. Shag RAS

4.2.1. National trend TIARG’s RAS is one of two active projects for Shag. The national trend is generated from two historical projects and TIARG’s project (and not the other active project as yet). The quality of the national trend is considered to be 'Uncertain'. As one project began the year after the previous two ended, it has been difficult to calculate appropriate confidence limits for the last few years. The long-term trend (1998-2017) is stable.

Figure 4. The RAS programme national trend in the apparent adult survival of Shag

4.2.2. TIARG RAS The trend in the apparent adult survival at the TIARG’s Shag RAS is shown in Figure 5. Interpretation of the trend is provided once in every three years by the British Trust for Ornithology, with the expectation of feedback in 2019.

A summary of the results for the TIARG Shag RAS study are presented in Table 2.

TIARG Annual Report 2018 v06/01/19 32

Figure 5. The trend in the apparent adult survival of Shag for the RAS study on Lunga

Table 2: Summary results for the Shag RAS studies for the two sexes

Shag RAS Males Females Estimate of average annual adult survival across all projects 78% 81% Estimate of average annual adult survival from TIARG project 83% 89% Estimate of TIARG project’s average annual recapture probability 63% 55%

5. Acknowledgements RAS is supported by a partnership between the BTO and the Joint Nature Conservation Committee (JNCC) on behalf of the country agencies (Natural England, Natural Resources Wales, Scottish Natural Heritage and the Department of Agriculture, Environment and Rural Affairs, Northern Ireland). It is also part of the BTO Ringing Scheme which is funded by the BTO/JNCC Partnership, The National Parks and Wildlife Service (Ireland) and the ringers themselves.

TIARG Annual Report 2018 v06/01/19 33

Treshnish Isles ringing totals 1971 – 2018

SPECIES 1971 1974 1976 1977 1978 1980 1982 1984 1986 1989 1991 1993 1994 1995 1996 1997 1998 1999 2000 Eider Fulmar 17 6 4 8 21 14 18 7 21 15 4 27 38 7 24 23 12 Manx Shearwater 2 13 4 4 1 8 9 1 2 1 4 4 Storm Petrel 254 22 1 283 203 800 411 975 75 440 536 331 1104 741 732 414 Shag 150 7 10 10 24 80 50 160 40 10 10 59 96 99 150 100 59 Buzzard 1 2 Corncrake Oystercatcher 1 1 4 2 2 Ringed Plover Common 1 Sandpiper Great Skua 1 Kittiwake 1 1 1 2 2 4 6 10 1 50 41 23 13 Common Gull 4 5 Lesser Black-b Gull Herring Gull 6 1 14 46 35 56 4 4 3 5 24 19 52 73 39 15 Great Black-b. Gull 3 6 3 7 6 22 14 35 22 15 6 25 16 48 19 16 2 Guillemot 32 20 14 66 502 137 364 180 250 306 109 498 349 472 503 507 892 Razorbill 65 72 90 115 266 218 236 151 103 64 81 101 105 98 112 102 133 Black Guillemot 1 Puffin 70 198 271 203 200 208 182 174 160 114 358 236 301 267 398 274 389 Hooded Crow Willow Warbler 1 Wren 3 Starling Stonechat Wheatear 12 1 3 5 24 37 22 50 Pied Wagtail 1 3 2 Meadow Pipit 4 1 12 Rock Pipit 5 1 2 4 2 4 2 1 Twite 2 TOTAL 343 567 439 17 441 1427 684 1266 1326 1014 1506 75 1029 1530 1267 2229 2109 1846 2001 NOTES: (1) Data for 1971 - 1995 extracted from Walker & Cooper (1996). This may not include all rings used. (2) Ringing data for a three-day visit in 1972 are not available.

TIARG Annual Report 2018 v06/01/19 34

Treshnish ringing totals 1971 – 2018 (continued)

SPECIES 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 Total Eider 1 1 Fulmar 25 22 25 47 14 15 8 1 1 1 425 Manx Shearwater 2 1 1 2 4 9 3 18 3 13 13 5 8 2 135 Storm Petrel 1030 15 360 83 491 962 21 118 403 293 202 212 191 448 978 258 289 426 14102 Shag 37 97 99 200 77 35 141 124 53 116 67 120 115 90 148 165 200 124 3123 Buzzard 3 Corncrake 1 2 3 Oystercatcher 1 4 2 2 1 2 1 4 1 28 Ringed Plover 1 1 1 3 Common 1 1 1 1 5 Sandpiper Great Skua 1 1 1 2 4 2 2 2 1 17 Kittiwake 11 3 2 21 15 14 16 3 4 3 8 16 12 14 22 11 330 Common Gull 11 11 6 16 8 4 1 1 67 Lesser Black-b Gull 1 2 2 4 1 10 Herring Gull 11 11 8 11 8 1 11 7 20 11 8 7 3 4 3 8 4 2 534 Great Black-b. Gull 27 5 21 18 12 3 4 13 12 15 10 4 1 2 15 11 16 2 456 Common Tern 1 1 Arctic Tern 44 104 16 11 175 Guillemot 312 425 261 800 141 172 123 1 51 53 169 46 8 145 154 161 230 327 8780 Razorbill 31 110 56 147 37 33 34 5 6 7 8 2 2 32 23 17 40 65 2767 Black Guillemot 1 2 Puffin 214 351 244 226 151 272 195 327 32 38 68 301 71 128 239 260 214 141 7495 Hooded Crow 1 1 Willow Warbler 1 2 Whitethroat 1 1 Sedge Warbler 2 2 Wren 1 2 4 2 2 1 1 2 6 2 1 3 2 32 Starling 3 1 4 Stonechat 2 1 3 Wheatear 24 2 2 2 7 1 2 4 2 4 5 10 4 7 11 3 3 3 250 Dunnock 1 1 1 2 5 Pied Wagtail 4 3 1 4 18 Meadow Pipit 1 4 1 3 5 1 4 1 2 15 3 1 5 1 64 Rock Pipit 2 2 2 2 3 21 10 1 2 4 3 1 2 11 1 4 2 94 Twite 1 1 1 1 3 1 10 TOTAL 1739 1060 1090 1563 982 1527 593 624 594 555 575 748 405 943 1729 930 1035 1122 38948 NOTES: (1) Ringing totals are not included for May and July 2018.

TIARG Annual Report 2018 v06/01/19 35

Recent ringing recoveries

STORM PETREL

TIARG have in the past year received details of 15 recoveries of birds ringed within Britain and Ireland in the months July - September and controlled by TIARG on Lunga in June - July 2017. These recoveries are summarised in the table below; all birds were ringed as adults (Euring code 4).

Ringing Site No. of controls at: Time interval (years, days) Distance Direction Lunga min Max Km (degrees)

Fair Isle, Shetland 1 2 yr 305 d 503 350

Porth Iago, Llyn Peninsula, 1 11 yr 366 d 419 345 Gwynedd

Bewan, North Ronaldsay, Orkney 2 340 d 348 d 401 217

Twinyess, North Ronaldsay, Orkney 1 8 yr 328 d 396 217

Burghead, Moray 1 337 d 222 233

Eilean nan Ron, Highland 2 1 yr 318 d 3 yr 335 d 262 209

Faraid Head, Highland 2 1 yr 1 d 2 yr 312 d 255 203

Fife Ness, Fife 2 333 d 11yr 346 d 238 276

Eilean An Taighe, Western Isles 2 361 d 7 yr 363 d 156 182

Ballyreagh, Londonderry 2 1 yr 350 d 2 yr 355 d 146 007

RECOVERIES OF OTHER SPECIES

All other recoveries relating to the Treshnish Isles received since the previous TIARG report are listed below.

Shag 1701609 1 29/6/2017 Lunga X 09/8/2017 Traigh na Cille, Kilninian, Isle of Mull, Argyll and Bute 13 km 74 degs 41 days Dead on strand line. Eaten.

Shag 1701590 1 29/6/2017 Lunga XF 03/1/2018 Isle of Barra, Western Isles 85 km 311 degs 188 days Freshly dead - within a week.

Shag 1483593 8 28/6/2015 Lunga S 13/3/2018 Scolpaig, North Uist 144 km 153 degs 986 days Re-sighting of a colour-ringed bird

Shag 1445789 1 25/6/2013 Lunga X 25/5/2018 An Snoig, Hynish, Isle of Tiree, Argyll and Bute 31 km 260 degs 1795 days Ring only found.

TIARG Annual Report 2018 v06/01/19 36

Great Black- backed Gull MA15802 1 02/7/2010 Lunga X 04/6/2018 Treshnish Isles 0 km 0 degs 2894 days Dead for more than a week, not fresh. Bird found.

Razorbil M77258 1 30/6/1996 Isle of Canna, near Mallaig, Highland R 25/6/2017 Lunga 64 km 174 degs 7665 days

Puffin ET80224 8 02/7/1998 Lunga XF 27/4/2018 Lunga 0 km 0 degs 7239 days Freshly dead - within about a week. Bird found half eaten.

Puffin EK29889 4 24/6/1991 Lunga X 27/6/2018 Lunga 0 km 0 degs 9865 days Dead for more than a week, leg and ring only found. Possibly taken by bird of prey.

Greylag Goose 5271924 4F 16/11/2017 Cornabus, Islay, Argyll and Bute S 07/2/2018 Cornabus, Islay S 16/3/2018 Cornabus, Islay S 28/6/2018 Bac Mór 92 km 350 degs 224 days Re-sighting by TIARG.

References

Harris, M.P., Heubeck, M., Newell, M.A. and Wanless, S. 2015. The need for year-specific correction factors when converting counts of individual common guillemots Uria aalge to breeding pairs. Bird Study 62: 276- 279.

Gilbert, G. & Helmsley, D., 1996. A survey of Storm Petrels (Hydrobates pelagicus) on the Treshnish Isles 1996. Unpublished RSPB report, September 1996.

JNCC. 2016. Seabird Population Trends and Causes of Change: 1986-2015 Report (http://jncc.defra.gov.uk/page-3201). Joint Nature Conservation Committee. Updated September 2016. Accessed 26/08/18.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E., 2004. Seabird populations of Britain and Ireland: results of the Seabird 2000 census. T. & A.D. Poyser, London.

Offer, D., 2000. Manx Shearwater Survey 2000. In Ward, R.M., 2000. Treshnish Isles Auk Ringing Group Report for 2000. Treshnish isles Auk Ringing Group.

Ottvall, R., 1999. Female Corncrake (Crex crex) singing in the wild. J. Ornithol. 140, 453-456.

Ratcliffe, N., Vaughan, D., Whyte, C. & Shepherd, M., 1998. The development of playback census methods for Storm Petrels (Hydrobates pelagicus) Bird Study 45:302-312.

TIARG Annual Report 2018 v06/01/19 37

Robinson, R.A., Leech, D.I. & Clark, J.A. 2016. The Online Demography Report: Bird ringing and nest recording in Britain & Ireland in 2016. BTO, Thetford (http://www.bto.org/ringing-report, created on 10- August-2017)

Walker, S. & Cooper, D., 1996. Birds on the Treshnish Isles 1971-1995. Unpublished report by the Treshnish Isles Auk Ringing Group.

Varham, K., 2008. Preventing rats becoming established on Nightingale Island: Recommendations for monitoring and contingency. In Report from Rat Eradication Workshop, Stanley, Falkland Islands, 08/09 September 2008 drafted by Clare Miller (RSPB).

Acknowledgements

Firstly, we would like to express our appreciation to the owners of the Treshnish Isles, THE HEBRIDEAN TRUST (www.hebrideantrust.org) for permission and funding to allow our continuing studies to be made on these fascinating islands.

We thank Iain Morrison and his family, for providing our transportation between Mull and Lunga, between the islands of the Treshnish Isles (http://www.turusmara.com/), and are grateful for his continuing advice, co- operation and help.

Any comments on this report, and suggestions for improvements for relaying information required by conservation agencies, are much welcomed.

Razorbill (Andrew Carter)

TIARG Annual Report 2018 v06/01/19 38

The Expeditions 1971 – 2018 A list of participants through the years, with brief notes on the work performed

1971 Barry Lawson, Peter Deans, John Eatough, Shiela Anderson, Dick Hansford. Full census and ringing. This was the first trip and the Treshnish Isles were included in a “mopping up” of islands not fully covered during the 1969/70 “Operation Seafarer” National Seabird Census.

1972 Barry Lawson, Geoff Ward, Bevan Craddock. Part census and ringing Forced to leave after three days due to bad weather.

1973 Barry Lawson, Peter Deans, John Hodson, Geoff Cope. Trip abandoned – unable to land due to rough seas

1974 Barry Lawson, Peter Deans, Geoff Ward, John Hodson, Geoff Cope, Tom Pool. Census of Lunga and ringing An RAF Helicopter landed a photographer onto Harp Rock, causing many bird casualties.

1976 Barry Lawson, Peter Deans, Geoff Ward, John Hodson, Geoff Cope, Tony Kilgallen. Full census Lunga – Fladda and ringing. Very hot summer.

1977 Barry Lawson, John Hodson. Ringing only. Called in on “Corryvreckan” boat cruise.

1978 Barry Lawson, Peter Deans, John Hodson, Simon Walker. Full census Lunga and Sgeir a’ Chaisteil and ringing.

1980 Barry Lawson, Peter Deans, John Hodson, Simon Walker, David Lawson. Ringing only

1981 Geoff Ward, Geoff Cope. Part census and photography

1982 Barry Lawson, Peter Deans, John Hodson, Simon Walker, Andrew Lawson. Ringing only.

1984 Barry Lawson, Peter Deans, John Hodson, Simon Walker. Ringing only.

1986 Barry Lawson, Peter Deans, Geoff Ward, John Hodson, Simon Walker, Andrew Lawson. Full census with ringing

1989 Barry Lawson, Peter Deans, John Hodson, Simon Walker. Ringing only.

1991 Barry Lawson, Peter Deans, Simon Walker, David & Andrew Lawson, Jan Densham. Ringing only.

1993 Roger Broad et al. (Scottish Natural Heritage charter) Full census of The Dutchman’s, Lunga, Sgeir a’ Chaisteil and Fladda. Chris Redfern et al. Storm Petrel ringing.

TIARG Annual Report 2018 v06/01/19 39

The Expeditions 1971 – 2018 (continued)

1994 Simon Walker, Mike Smith, Dennis Cooper, Jan Densham, Danny Lenain. Full census Lunga and Sgeir a’ Chaisteil and ringing. Chris Redfern et al. Storm Petrel ringing. 1995 Simon Walker, Mike Smith, Dennis Cooper, Jan Densham, Fergus Henderson. Full census of Lunga and Sgeir a’ Chaisteil and ringing.

1996 Simon Walker, Mike Smith, Dennis Cooper, Danny Lenain, Robin Ward Full census of Lunga and Sgeir a’ Chaisteil and ringing.

1997 Simon Walker, Dennis Cooper, Robin Ward, Damian Offer, Steve Willis, Chris Spray Full census of Lunga – Fladda and ringing.

1998 Simon Walker, John Hodson, Dennis Cooper, Robin Ward, Damian Offer, Steve Willis, Steve Worwood Full census of Lunga – Fladda and ringing.

1999 Week 1 Simon Walker, Dennis Cooper, Steve Willis, John Osbourne. Week 2 Simon Walker, John Hodson, Dennis Cooper, Robin Ward, Damian Offer, Jan Densham Full census of the Treshnish Isles for Seabird 2000 and ringing 2000 Week 1 John Hodson, Dennis Cooper, Damian Offer Full census of Manx Shearwater on Lunga for Seabird 2000. Limited passerine ringing. (May). Week 2 Simon Walker, John Hodson, Dennis Cooper, Robin Ward, Steve Willis, Andrew Carter, Steve Woodward Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Tern census for Seabird 2000. Ringing.

2001 Simon Walker, John Hodson, Dennis Cooper, Robin Ward, Damian Offer, Andrew Carter Completion of census for Seabird 2000. Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2002 Simon Walker, Robin Ward, Andrew Carter, Phil Bone, Sara Brown, Jackie Hay. Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2003 Simon Walker, John Hodson, Dennis Cooper, Robin Ward, Andrew Carter, Jackie Hay, Matt Smith. Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2004 Simon Walker, Robin Ward, Andrew Carter, John Calladine, Tim Dixon, Shaun Micklewright, Tina Wiffen. Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2005 Simon Walker, Robin Ward, Andrew Carter, Shaun Micklewright, Gareth Harris, George Henderson, Tracé Williams. Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2006 Simon Walker, Dennis Cooper, Robin Ward, Andrew Carter, Shaun Micklewright, John Calladine, Tim Dixon, George Henderson. Full census of Lunga, Sgeir a’ Chaisteil, Cairn na Burgh More, Cairn na Burgh Beg and the islands between Lunga – Fladda. Ringing.

TIARG Annual Report 2018 v06/01/19 40

The Expeditions 1971 – 2018 (continued)

2007 Simon Walker, Robin Ward, Andrew Carter, Shaun Micklewright, George Henderson, Tim Dixon, Tracé Williams. Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2008 Simon Walker, John Hodson, Robin Ward, Andrew Carter, Shaun Micklewright, George Henderson, Tim Dixon, John Calladine. Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2009 John Hodson, Robin Ward, Dennis Cooper, Andrew Carter, Shaun Micklewright, Tim Dixon, Jurjen Annen, Claire Dovey. Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2010 John Hodson, Robin Ward, Andrew Carter, Shaun Micklewright, Tim Dixon, Tracé Williams Jurjen Annen, Claire Dovey. Full census of Lunga, Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2011 John Hodson, Robin Ward, Andrew Carter, Shaun Micklewright, Tim Dixon, George Henderson, Jurjen Annen, Claire Dovey. Full census of Lunga, Sgeir a’ Chaisteil, Bac Mór (from boat) and Bac Beag (from boat). Ringing.

2012 John Hodson, Robin Ward, Dennis Cooper, Tim Dixon, Steve Willis, Jurjen Annen, Claire Dovey, Richard Barnes, Simon Roberts. Full census of Lunga and Sgeir a’ Chaisteil. Ringing.

2013 John Hodson, Robin Ward, Dennis Cooper, Andrew Carter, Tim Dixon, Shaun Micklewright, Jurjen Annen, George Henderson. Full census of Lunga and Sgeir a’ Chaisteil. Ringing.

2014 John Hodson, Robin Ward, Andrew Carter, Tim Dixon, Shaun Micklewright, Jurjen Annen, Claire Dovey, Cerian Thomas. Full census of Lunga and Sgeir a’ Chaisteil. Ringing.

2015 Robin Ward, Andrew Carter, Tim Dixon, Shaun Micklewright, John Calladine, Stuart Brown, Chris Heward, Daniel Plunkett. Full census of Lunga and Sgeir a’ Chaisteil and the islands between Lunga – Fladda. Ringing.

2016 Robin Ward, Andrew Carter, Tim Dixon, Jurjen Annen, Chris Heward, Daniel Plunkett, Matt Smith, Lila Buckingham. Full census of Lunga, Sgeir a’ Chaisteil, Cairn na Burgh More, Cairn na Burgh Beg and the islands between Lunga – Fladda. Ringing.

2017 Robin Ward, Andrew Carter, Tim Dixon, Shaun Micklewright, George Henderson, Claire Dovey, Chris Heward, Lila Buckingham. Full census of Lunga, Sgeir a’ Chaisteil, Bac Mór (from boat), Bac Beag (from boat) and the islands between Lunga – Fladda. Ringing. 2018 May Dennis Cooper, Tim Dixon, Jamie Dixon, Ross Johns, Matt Williams (For 24 hours: Robin & Judith Ward). Full census of Manx Shearwater on Lunga for Seabirds Count. Limited ringing. (1 week). June Robin Ward, Andrew Carter, Tim Dixon, Shaun Micklewright, Jurjen Annen, Chris Heward, Lila Buckingham, Emma Hughes. Full census of the Treshnish Isles for Seabirds Count. Ringing. (1 week) July Dennis Cooper, Tim Dixon, Chris Heward, Lila Buckingham, Daniel Plunkett, Jamie Dixon, Matt Williams, Nicci Cox, Carole Davis, Jacki Gittins, Thomas Hibbert, Peter Robinson, Chris Smith, Helen Stace. Full census of Storm Petrel on the Treshnish Isles for Seabirds Count. Limited ringing. (2 weeks).

TIARG Annual Report 2018 v06/01/19 41

Ring series used on the Treshnish Isles since 1927*

SHAG RINGS A2 RINGS E RINGS F RINGS G RINGS H RINGS RAZORBILL GUILLEMOT MISC. RINGS RINGS RINGS 1078761 – 800 2010581 – 583 EF75001 – 500 FA50601 - 700 GH21301 – 350 HT03619 K10701 – 1000 R07001 – 100 1F4094 - 097 1080101 – 110 2101991 – 2000 EG23501 – 700 FB22601 – 700 GN85301 – 400 HT09001 – 004 K13001 – 300 R19401 – 20200 C331894 - 900 1087111 – 120 2121401 – 500 EG23721 – 780 FB23401 – 500 GJ35401 – 500 HT17871 – 890 M36341 – 350 R24001 – 26350 E196501 - 520 1105561 – 570 2167051 – 068 EG23801 – 999 FC52551 – 558 GJ76001 – 800 HT17931 – 940 M46501 – 800 R31601 – 900 JB44316 1123531 – 540 2170201 – 203 EG61000 – 500 FC52571 GJ99081 – 082 HT34021 – 030 M55001 – 500 R51501 – 2000 K039209 - 230 1123541 – 550 2238501 – 600 EG88501 – 9000 FC74501 GK34351 – 354 HT68201 – 210 M72451 – 800 R65501 – 6000 K419290 - 295 1123671 – 690 2261001 – 2350 EH33377 – 380 FH36101 – 200 GK50214 – 220 HT68221 – 226 M85501 – 800 R72501 – 4000 NA84296 - 299 1123961 – 970 2284001 – 5000 EH54501 – 55000 FR13606 – 636 GK50551 – 570 HT80301 – 400 M88001 – 300 T14001 – 5000 KX83101 - 106 1130701 - 800 2309901 – 10000 EH89256 FR14401 – 500 GK62985 – 990 HW05351 – 360 M92501 – 700 R73001 – 4000 KX83116 - 118 1159651 – 700 2311301 – 400 EH89260 FR51201 – 300 GK90821 – 840 HW06951 – 7000 T82001 – 300 RF10011-020 1163701 – 740 2311501 – 2000 EH98001 – 300 FR56351 – 400 GK91471 – 490 HW08994 – 09000 X39501 – 40000 LA59201-300 1168001 – 100 2348001 – 500 EK29501 – 900 FR76701 = 800 GM78756 HW37361 X56501 – 57000 DD90261-270 1170601 – 700 2236801 – 7000 EK72657 – 660 FS21478 GP13416 – 450 HW42996 - 3000 X63001 – 500 CBV601-700 1174201 - 300 2369301 – 400 EK91471 – 490 FS51016 – 500 GP47917 HW68101 – 110 X67501 – 68000 V711401-500 1187901 – 950 2405001 – 6000 EL19801 – 276 FS87001 – 100 GP62201 – 207 HW68161 – 170 X79501 – 80000 TJ18901-9000 1237401 – 450 2430701 – 900 EL52501 – 3000 FV10611 – 620 GP74501 – 75000 HW74971 – 990 X99001 – 500 BT09481-490 1322951 – 960 2436501 – 7000 EN22001 – 500 FV10646 – 650 GR44201 – 250 HW87211 – 225 Y09403 – 405 NV42851-860 1328481 – 490 2444501 – 5000 EP85608 – 612 FV54446 – 460 HW96181 - 200 SR49601-700 1350801 – 900 2446202 – 233 EP85687 – 700 FV62410 HW94907 – 913 A297482-500 1357901 – 8000 2455501 – 6000 ER03701 – 800 FV62416 – 226 MA12551 – 600 B229951-992 1366901 – 7000 2480001 – 500 ER48401 – 404 FV96681 – 684 MA15801 – 900 BV70669 1373751 – 3900 2513501 – 4000 ES64018 – 189 SS96101 – 300 A2 RINGS MA44251 – 900 SV58551-600 1378401 – 8500 2538001 – 800 ET19501 – 700 (cont) BV28661-670 1399601 – 700 2542001 – 3000 ET52501 – 3000 2664001 – 5000 SHAG RINGS SV58601-616 1408301 – 500 2554001 – 500 ET80001 – 500 2679001 – 80000 (cont) Z155001-100 1414301 – 500 2560001 – 1000 EW18001 – 500 2725001 – 6000 1497001 – 100 EL69255-300 1421701 – 800 2579001–80000 EW50001 – 500 640801 – 640900 1500201 - 300 1417001 – 7100 2605001 – 5500 EX12501 – 3000 2627701 - 800 1701501 - 2000 1445601 – 800 2624001 – 5000 EY32001 - 500 1118766 - 789 1491001 – 100 2650101 – 61000 EZ30001 – 1000 *All rings series known (to TIARG) to have been used on the Treshnish Isles are documented irrespective of ring ownership.

TIARG Annual Report 2018 v06/01/19 42